| Why
Save Endangered Species?
Why Save Endangered Species? Since life began on this planet, countless creatures have come and gone - rendered extinct by naturally changing physical and biological conditions. Since extinction is part of the natural order, some people ask: "Why save endangered species? Why should we spend money and effort to conserve them? How does society benefit from protecting them? Congress addressed these questions in the preamble to the Endangered Species Act of 1973, recognizing that endangered species of fish, wildlife, and plants " are of esthetic, ecological, educational, historical, recreational, and scientific value to the Nation and its people." In this statement, Congress summarized a number of convincing arguments advanced by scientists, conservationists, and others who are greatly concerned by the disappearance of unique creatures. Congress further stated its intent to provide a mechanism to conserve the ecosystems upon which endangered and threatened species depend in order to prevent their extinction. While extinctions do occur naturally, scientific evidence strongly suggests that the current rate of extinction is much higher than the natural rate - about 1,000 times higher than it was before humans appeared on Earth. Some scientists estimate that this rate may multiply by 10 over the next hundred years, largely because of modern human activity. The primary force driving this loss is habitat destruction. Exploitation, the introduction of exotic (non-native) organisms and the spread of disease also pose significant risks to the planet's biological heritage. Conservation actions resulting from the Endangered Species Act have successfully prevented 99 percent of the species listed as endangered or threatened from extinction. However, humans are still exterminating species on a global scale at ever-increasing rates. The previous mass extinction event in North, Central, and South America 11,000 years ago resulted from stress due to climate and habitat change and the arrival of humans. This combination of factors resulted in the extinction of 100 bird and large mammal species. By contrast, biologists now estimate that since the Pilgrims landed at Plymouth Rock in 1620, more than 500 species, subspecies, and varieties of our Nation's plants and animals are thought to have become extinct. The situation in the Earth's most biologically rich ecosystems is worse. Tropical rainforests, which may contain up to one half of all living species, are losing more than 38 million acres per year. Uncounted species are lost as these acres disappear. The Benefits of Natural Diversity While scientists have classified approximately 1.7 million organisms, it is estimated that between 10 and 100 million species inhabit the planet. All of these living creatures, including humans, are part of a complex, delicately balanced network called the biosphere. This narrow zone of life is composed of many ecosystems, each with its own complement of plants and animals and their biological, chemical, and geological processes and interrelationships that characterize them. No creature exists in isolation. Therefore, the removal of a single species can set off a chain reaction affecting many others. The full significance of the extinction of a species is seldom apparent; much remains to be learned, and the long-term impacts are difficult to predict. Medicine Every species contains a unique storehouse of genetic material that has evolved over eons of time. Once lost, this genetic fingerprint cannot be duplicated. Scientists have only investigated about 2 percent of the more than 250,000 known plant species for possible medicinal values. The chemical secrets of most species have yet to be unraveled for potential benefits to mankind. No matter how small or obscure a species, it could one day help all of us. A fungus that originally gave us both the anti-bacterial medicine penicillin and cyclosporin A has dramatically increased the success of organ transplant operations. The recently discovered compound taxol was first isolated from the Pacific yew, a small tree of America's old-growth forests in the Pacific northwest. Taxol has been found to be an effective treatment for ovarian, breast, and other types of cancer. Nearly 40 percent of all medical prescriptions dispensed annually in the United States have been derived from nature or synthesized to mimic naturally occurring chemical compounds. The American Cancer Society says that men have a 1 in 2 and women a 1 in 3 lifetime chance of developing cancer. The National AIDS Clearinghouse says that between 650,000 and 950,000 Americans are HIV positive. These facts are sobering when one realizes that with the extinction of every species we may be throwing away the key that could unlock the effective treatment of these and other devastating diseases.
Agriculture Many seemingly insignificant forms of life are beginning to show important benefits in agriculture. Some farmers are beginning to use insects and other animals that compete with or prey on certain crop pests, as well as using plants containing natural toxic compounds that repel harmful insects. These are called "biological controls," and in many cases they are a safe, effective, and less expensive alternative to synthetic chemicals. The Lake Placid mint, an endangered species known only from central Florida, may have benefits to crop production because it produces a potent chemical that repels insects, including ants. One species, the running buffalo clover, an endangered species once believed to be extinct, is now being screened as a possible forage crop because of its higher protein content and perennial nature. Thomas Jefferson once wrote that "the greatest service which can be rendered any country is to add a useful plant to its culture, especially a breadgrain." It has been estimated that there are 80,000 species of edible plants, of which fewer than 20 produce 90 percent of the world's food. If under-utilized species are conserved, they could help to feed millions of people who go to bed hungry each night. One grain native to the Great Lakes States, Indian wild rice, is superior in protein to most domesticated rice, and its commercial production is earning millions of dollars annually. Crossing it with a related but endangered species, Texas wild rice, might result in a variety adaptable to other regions. Plant collectors are now seeking out remaining wild strains of many common crops, such as wheat and corn, for work on new hybrids more resistant to crop diseases, pests, and marginal climatic conditions. Two thirds of U.S. plant species of conservation concern are closely related to cultivated crops. Industry is also increasingly making use of wild plants. Two species in particular that show potential are the jojoba and the guayule. The jojoba produces an oil with many unique properties that have application to a variety of industrial processes. In the past, the only comparable oil was derived from the sperm whale, but over-harvesting brought this great marine mammal to the brink of extinction. The guayule is a shrub containing high amounts of natural rubber, as well as a resin rich in other valuable substances. Both plants grow in the deserts of the southwestern United States, giving economic value to lands not suitable for other agricultural purposes, and they could provide domestic sources of products that would otherwise have to be imported.
| |
